Age datums, and abundance of Discoaster brouweri and Coccolithus pelagicus in ODP Site 180-1115 sediments

Surface waters were mostly warm during the early Pliocene with a slightly cooler interval centered on 4.5 Ma. A more pronounced cool interval occurred at ~3.2 Ma.

The early and mid-Pliocene cool periods may reflect Antarctic glacial growth. A mid-Pliocene warm interval occurred from ~3.1 to 2.8 Ma. Temperature began to decline beginning ~2.7 Ma, marking the onset of Northern Hemisphere glaciation.